Figuring out how to stop nutrients from fertiliser and animal wastes flowing from land into waterways is difficult, as it isn’t a question only of farming intensity, but also soil type, topography, groundcover, and a host of other variables.
Now, a new software tool called LUCI—it’s short for Land Utilisation and Capability Indicator—can help predict run-off and offer solutions.
Developed by Victoria University of Wellington researcher Bethanna Jackson (pictured), LUCI uses a farm’s geographic information system (GIS) data to estimate how much nutrient is entering nearby waterways. It does this by measuring ground cover, animal numbers, fertiliser amounts, slope, and soil types, in resolution up to five metres. Then it calculates the flow of water across and under farmland, and how much rain each part of the land can absorb.
With this data, LUCI can predict how many animals each part of a farm can hold, and how much fertiliser can be applied, before run-off occurs. It also highlights areas where water could be slowed by features such as sediment traps, planting, or changes to tillage. If adopted widely, LUCI could later be used to predict the health of rivers and streams.